noun
written recommendation; letter of recommendation; nomination letter
Refers to a formal document that recommends or nominates someone, such as for a job, school, or award.
大学院に出願するために、教授に推薦書を書いてもらった。
I had my professor write a letter of recommendation for my graduate school application.
この賞の候補者には、推薦書が必要です。
A nomination letter is required for candidates for this award.
Compound of 推薦 (recommendation) + 書 (document).